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1994 Minicab Starting Problem

Discussion in 'Mitsubishi Minicab' started by Bill_G, Apr 20, 2023.

  1. Bill_G

    Bill_G New Member

    Hi Guys,

    I am having a problem with my 1994 Mit Mini Cab. I've had the truck since 2008 and have used it very little. It has always been stored in a garage.The truck has a 4 speed manual trans and has ~42k kilometers on the odometer. Not sure of the model, but will check that later this week when I travel back to my old home place. Normally, I try to start the truck and let it run periodically. But, it has been a couple of years since I've had it running.

    I am in the process of moving out of state and when I tried starting the truck last week, it would start and run for 5-10 seconds and stop. Like it was running out of fuel. I added fresh gas and the gauge currently shows 1/2 tank. When I hit the starter again, the engine will turn over, but not attempt to start. If I pump the accelerator several times and let it set for 10-15 minutes, it will start immediately and run for 5-10 seconds, but the engine will stop again. You can rinse and repeat.

    I had the truck running and drove it a short distance a couple of years ago. When I parked it, I added Stabil to the fuel and a small amout of 50 to 1 chain saw premix, just to lube the cylinders before turning the engine off. I have never worked on the engine and am totally unfamiliar with how to even get to it to check the carb. I have rasied the seats and can see the top of the engine but haven't spent much time other than that. I am hoping the seats and seat frame will come off to allow access to top of the engine and carburetor. I suspect I will also need to check the fuel filter, etc. Not sure if it has an in-tank pump, but will try to figure that out when I am up there tomorrow. Fortunately, I am familiar with gas engines and maintained my own for serveral years.

    Any thoughts or suggestions are greatly appreciated.

    Thanks in advance.

    Bill
     
  2. Bill_G

    Bill_G New Member

    I spent some time with the truck last Friday/Saturday. Based on the plate located under the passenger side seat, the truck model is U19T HFD and an engine code 3G83.

    I found the fuel pump and filter, which was located along the inner rail on the drivers side. When I disconnected the line from the tank to the filter inlet, gas begin pouring out of the tank side. I then disconnected the filter outlet hose and gas gushed out of that side, as well. When I disconnected the outlet side of the fuel pump and turned the engine over, a stream of gas shot out of the pump. So, I think the fuel pump and filter may be okay. I also noticed that when the ignition key was turned to the "On" position, as small spray of gas shot out of the pump. From what I have read, I believe this is to build fuel pressure for starting the engine and is normal.

    Although I don't believe it is a spark problem, I removed the distributor cap and rotor and cleaned the terminals inside the cap. The rotor looked fine. When I reconnected the fuel lines and put the distributor cap back on, I pumped the gas pedal serveral times and tried to start the engine. It would not even hit, or try to start. After letting it sit for 15-20 minutes, I tried starting again and it started immediately, but only ran for 4-5 seconds and died, like the fuel was turned off.

    When I traced the fuel lines from the tank toward the engine compartment, I noticed two small canisters located on the outside of the frame rail, right behind the drivers side door. I am thinking these may be emmission vents or canisters, but am not sure (if I can figure out how to attach pictures, I will add these, along with a picture of the fuel pump and filter to this thread). Anyway, I reduced the outlet pressure on my air compressor and removed the tank side line and put low pressure air toward the tank. It seemed clear. The hose towward the engine would not accept air, as though it was blocked. Not sure if this is normal?

    So, I am right back where I started. During the short duration the engine is running, it idles smooth with no roughness or missing.

    Again, any thoughts or suggestions are appreciated.
     
    Last edited: Apr 24, 2023
  3. Bill_G

    Bill_G New Member

    Canisters 2.jpg Pump And Filter 2.jpg
    Canisters and Fuel Pump/Filter
     

    Attached Files:

  4. MikeD

    MikeD Member

    This sounds silly but I've had a lot of luck with an additive called mechanic in a bottle . My old boss said it's the best employee we had =] home Depot sells it and some auto stores,dump the whole damn bottle in lol

    It sounds like you checked the obvious stuff. We need air ,fuel , spark , and compression to run .

    Sound like you've got fuel

    Since it runs sometimes without issue id say you prob have decent compression.

    Check air filter for mouse nest

    Could buy a cheap inline spark tester and check spark .


    When it does run. What causes it to die , does it just sputter out ? Do you use ethanol free fuel ? After that much time the ethanol will break down and being to gunk up everything.

    Get it running and rev it up , let her rip and burn off all the cobwebs with some of that fuel additive. Keep it alive as long as you can .Let it sit overnight and try again .
     
    Last edited: Apr 26, 2023
  5. Bill_G

    Bill_G New Member

    Mike, I really appreciate your input, thank you. I will pick up a bottle of the additive you suggested. Hoping one of the local auto stores have it

    I haven't taken the breather off to check the air filter, but will do so tomorrow. The garage the truck is stored in has been known to have mice and plenty of mud wasps, a nest is certainly a possibility. I will pull the breather tomorrow as well.

    When the engine starts, it runs completely smooth, no missing, sputtering, etc. It runs for a few seconds and it's like you turn the key off or shut the fuel off, it simply stops running. Unfortunately, there is no local source for non ethanol fuel. I am very familiar with the downside of ethanol and use additives in an attempt to control moisture and other contaminates. However, the fuel I am using could very possibly have caused problems in the carb.

    I was thinking about it last night, wondering if something may have built a nest in the exhaust pipe, causing back pressure when the engine is running. Not sure how likely that is, but I guess it's possible.

    My back is against the wall as I need to get it loaded for a four hour ride to the new property. There is a local gentleman with a 53 foot rollback that will be hauling it and a couple of tractors for me.

    Anyway, I really appreciate your taking time to offer your thoughts and will keep you posted.

    Bill
     
  6. MikeD

    MikeD Member

    They're going to laugh when you ask for that mechanic in a bottle.

    After reading your most recent comment I wonder if it's electrical. Of course this is just a guessing game from my end .


    The fact that the engine does run without issue for some time makes me think it must be getting air and fuel and has decent compression. Fuel is still a concern but maybe a cheap inline spark tester . You unplug the boot and plug the tester in line.

    When the engine dies out , if it has spark still you would the tester flashing

    If it dies out and those lights go out then your up against a spark /electric issue .


    To solve your problem could you just winch or push the vehicle onto the trailer ? Maybe a cheap harbor freight come-along winch and tow strap to hand winch it on to trailer

    Happy to help diagnose further if you want to bounce ideas around
     
  7. Bill_G

    Bill_G New Member

    Thanks Mike.

    Sounds like maybe I should hold off a bit on picking up the Mechanic in a Bottle additive. At least until I get an in-line spark tester. I checked online and see that the local Autozone has one. The reviews aren't good for this particular tester, but perhaps it will do what I need.

    I am at my old place today and tomorrow, so I will set aside some time to pick up an IL tester and check the breather/filter for nests, etc. I may pull the hoses off those emissions canisters, too. Just to make sure they are not clogged with something. The part really seems strange to me is the fact that I can consistently get it started by pumping the gas pedal several times, wait a few minutes, try to start it and it starts immediately as soon as I hit the starter.

    It should be easy enough to eliminate a spark issue by picking up a tester, as you suggested. That will remove one factor from the equation.

    If we can't get the thing running, my only other option will be using a tow strap, like you mentioned. I should be able to pull in on the trailer with one of the tractors that's going. I kinda hate to take that route due to delaying the driver while I mess with it. Would also have to get creative unloading and moving the truck on the other end.

    I will let you know what I find today, regarding the spark and the other things I look at.

    I really appreciate all your help!

    Thanks again.
     
  8. MikeD

    MikeD Member

    Yeah this will be a tough one to figure out . My gut tells me fuel but I could also see it being a spark issue based ok the way you said it runs fine sometimes and then just dies. What motor does your truck have ,Is it carbureted ?

    If it does have carburetor I lean even more to a fuel issue since that gas probably gunked up a bit over the last year

    The problem is it sounds like you don't have much more time to make sense of it.


    Need fuel , air , spark , and compression. Keep narrowing it down.




    Those inline spark testers are good enough only problem is it doesn't really take much to get them to light up. A good tester had a way to create a gap so the current has to work a little hard to jump the gap and light up the tester .
     
  9. MikeD

    MikeD Member

    So I've got a background in small engine repair , mostly commerical mowers
    I don't have any experience with these rigs . I officially get the title for my U44V bravo today.

    That being said. How hard is it to get at the fuel pump in your vehicle. Do these trucks have any little trap doors to get at it easily from above or do we need to drop the tank ? I don't know. There's really not a lot of good Info out there on these rigs.
     
  10. Bill_G

    Bill_G New Member

    Sounds like you are about to gain some experience in the mini truck business. Congrats on your U44V Bravo!

    Mine has a carburetor engine, engine code 3G83. Access to the fuel pump and filter is fairly easy. It is an electric pump, mounted along the inner frame rail on the driver side, just in front of the rear wheel. Access to the carburetor is not as straightforward. The front of the engine sits under the two seats, which lift up for access. Trouble is, there is hardly any clearance to access the carb. In the model I have, it is located right under the high/low range and e brake support frame. There is a bolted access hatch in the bottom front of the bed, which provides access to the rear part of the engine. The carb sits almost under the rear of the cab. Definitely made for a smaller person and I am 6'4. The truck is really too small for me, thus has had very little use. I doubt that I have put over 100 miles on it since purchasing in 2008. I have never had the first problem with it over the years. Therefore, I have no experience working on it. The truck has always been garaged since I've had it. During the first couple of years, I drove it some on the gravel back roads around where I lived. Eventually, I decided it was too small for me and purchased a Honda side x side. The truck has sit in the garage for the last 10 or 12 years, getting started and drove around in the yard every year or two.

    I did have a chance to pull the breather off and look under the air filter this morning. Didn't see any obstruction, nests, etc. I did not make it to town for the spark tester, though. May be able to do that tomorrow. I am inclined to agree with your thought on the probability that the problem is fuel related. If I could find a fuel pump at a reasonable cost, it would be simple to eliminate that from the equation.
     
  11. MikeD

    MikeD Member

    Oh that's cool, I didn't realize the fuel pump was outside of the tank. I wonder if mine is like that !


    Based on the vehicles history I would still focus on something either fuel or electrical related. Fuel broke down and rotted something out or a critter chewed something up maybe.

    They exciting part is it does run for a little bit. Could you get it running long enough to get it on the trailer?? Maybe use your side by side to push the mini truck onto the trailer?

    When it does run, can you rev it up or will it just die if you give it throttle?
     
  12. Bill_G

    Bill_G New Member

    Hopefully, yours has an external fuel pump, as well. Makes it so much easier to work with. Based on what I have read, I believe some of the trucks do have an in-tank pump.

    I am wondering if an electrical problem could be as consistent. In your experience, does it sound like a coil issue or distributor problem would consitently allow the engine to start and run for a few seconds and stop? That part of the problem is completely predictable, after pumping the accelerator and letting the truck sit for a period, it starts immediately upon turning the starter over. Not sure if there is a resistor(s) somewhere in the circuit that could be breaking down?

    I have been starting the engine standing outside the driver's door, it has the brake set and the transmission in neutral. So, I really don't know if it will rev up by pushing the accelerator - something else I need to try. It runs so briefly, that I wouldn't have time to get it loaded. The engine consitently runs no longer that 5-10 seconds before it stops. If I run out of time and have no other options, I will have to try loading with a tow strap or chain.

    I haven't sold my property yet, so I have a few weeks to resolve the problem. One of the neighbors has told me he will take the property at the price I quoted, pending review of the home. So, I have been working to get it ready for showing. Just juggling a lot of things right now, which makes the truck issue more inconvenient.

    I had to drive back home today, but will order a better inline spark tester and have it delivered prior to returning late next week. In the meantime, I will look around to see if I can find a fuel pump and filter that doesn't cost a fortune. I know the pump is putting out fuel, but I don't know if it building and maintaining the required pressure, as it should. When the truck runs, it's almost like it consumes the available fuel from the carburetor bowl and dies. Seems like pumping the gas and letting it sit for several minutes allows the fuel to be replinished and it will start again for a few seconds. I don't know if that even makes sense, but that's what it seems like. My suspicion is that it is either fuel delivery or the carburetor causing the problem. Could be wrong, though.

    Anyway, I hope your truck serves you well and you have many years of enjoyment with it.

    Thanks again for your thoughts and input.
     
  13. MikeD

    MikeD Member

    It's a guessing game until you can test for spark but you're right the odds lean towards fuel based on vehicle history. The symptoms could relate to a handful of things though

    Some people frown on this option but a quick way you could narrow things down would be to get some carb cleaner ( NOT started fluid) and remove your air box. Right when the engine starts to die shoot some cleaner in the carb and maybe give a little throttle to see if it comes back to life or still continues to die out . If it stays running on fluid than fuel delivery is your problem. If it still dies than you lean more towards electrical. Just be careful if you do this and keep fire extinguisher nearby.
     
  14. Bill_G

    Bill_G New Member

    Looking at spark testers at Amazon. I am thinking about the length of wire required to reach each of the spark plugs from the distributor. Do you know if they all include a test wire long enough to reach each spark plug?

    I ordered a fuel pump pressure test gauge, it should be here by Tuesday. That should help determine if the fuel pump is defective. Your idea about using carb cleaner sounds like it may work, though I am a litte concerned about starting a fire (as you mentioned). The altenator is mounted almost directly below the carburetor, so I would have to be really careful (would hate to burn the garage down). When I am up there next week, I will take a look at it again to see if it is feasible, without risking a fire.

    Did you get your Bravo home?

    Thanks for your help.
     
  15. MikeD

    MikeD Member

    So the spark tester just gets installed in-line. So you pop the boot off the spark plug , then you'll install the tester into the boot and the other end onto the plug.

    I did notice today on the 4a30 motor that the plugs are deep down in there so hopefully the tester can reach into the plug. I can see that being a potential problem, the spark tube is pretty narrow and deep at least on the 4a30 motor.


    The carb clean technique isn't really as sketchy as it sounds but certainly proceed at your own risk.

    We need more info on these trucks , these forums are very limited but I'm sure your not the only one out there with that issue.

    My bravo was out on the road today but man something seems wrong , it has no power at all and seems to have an issue ....
    Idles and revs good but just very sluggish in gear...I'm thinking maybe injectors and I'm hoping it's not a blown head gasket or something affecting compression. I'm starting a forum on here to document the progress of bringing it back to life
     
  16. Bill_G

    Bill_G New Member

    The plugs in my engine appear to set fairly deep, too. Not sure what I was thinking, but I assumed that one end connected to the distributor cap, thanks for clarifying. Sounds like I will need a tester with a straight boot connector.

    Sorry to hear about your Bravo. Hopefully, it is something simple and an easy fix. I am not sure how well the various injector cleaners that are on the market work. Or, if something like that would even help. I've always heard that an engine with low compression is difficult to start. Not sure that always holds true, though.

    Good thought about documenting your progress. Maybe someone who has experienced a similar problem will provide input. If not, at least your documentation may help someone else later on.

    It appears that the older model engines, like mine, are getting difficult to find replacement parts for. I looked for a new fuel pump today (online) and all were discontinued or unavailable. Out of curiosity, I also searched for a new or rebuilt carburetor, but was unable to find anything. Someone on the forum indicated that the engine in my truck was used on some of the Toro commercial mowers. But, I couldn't find anything that resembled the carb on my engine. I expect them to be pricey, if by some chance I could find one. If my truck was in rough shape, I wouldn't spend a lot more time on it. It's a pretty clean little truck, though.
     
    Last edited: Apr 30, 2023
  17. MikeD

    MikeD Member

    Reporting back to say my lack of power was related to old fuel and nasty filter. Few tanks of 91 + seafoam and other additives and it's back to normal.
     
  18. Bill_G

    Bill_G New Member

    Thanks for the update. Glad to hear you were able to correct the issue without a lot of work/parts, etc. A lot of people recommend Seafoam, so it must be good stuff.

    I checked everything I could think of on my minicab and was still unable to resolve the problem. I have set it aside for the last few weeks due to the heat, and the fact that I finished working on the place, getting it ready to sell. At this point, the property is sold and I need to have all my stuff out by Nov. 1.

    Before stopping work on it, I did order a new fuel pump and filter, simply out of desperation. Needless to say, neither helped the problem. On the bright side, I spoke to one of the techs at G&R Imports, who verified that this specific engine had a fuel shut-off module. I strongly suspect that is the culprit, but did not have a chance to test it, yet. Just looking at it from the top of the carb, it looks like a real pain to get to. Will have to go down that road when the hot weather breaks.

    Best of luck with your Bravo. Hopefully, you get many years of service out of it.
     
  19. MikeD

    MikeD Member


    Wow what a doozie, sad to hear you can't get it going yet
    >> Yes Seafoam is very good but it's not meant for bad gas. It treats ethanol sure but it's more to help burn carbon off valves
    >> Mechanic in a bottle is sold at home depot, it sounds silly but I've had it bring back many-a old sad engines with bad fuel.


    They are correct, there is a fuel shut off. Can you remind me what motor you have, the A430? I believe you may have the previous gen motor. I do have an electrical diagram for the a430 , I was just pawing through it yesterday and saw the fuel shutoff solenoid. It sucks how hard it is to get your hands on stuff. I also noticed mine had a second smaller fuel filter on the ( possibly?) return fuel line back to the tank? It was a small disc style that I haven't changed yet.



    Sorry for not reading through the previous post but have you tried to just spray some carb cleaner ( not starter fluid ) directly into the air intake while turning the key over? Just to help determine if fuel delivery is the problem or something else? This would eliminate everything fuel and electrical related as you're just directly spraying something combustible into the intake. You could even buy a small marine fuel tank than you could put up on the passenger seat and run the fuel line directly to the carb, but a fuel shut off solenoid would still limit this technique from working.
    >> Is the solenoid attached right to the bowl of the carb? you may also be able to just supply it with power ?

    Sorry for all of the unorganized thoughts, just thinking out loud. I have a lot of experience on small engine repair, just not this particular small engine =[
     
  20. MikeD

    MikeD Member

    I really doubt this helps, this is from the electrical manual on the 1990-1998 Bravo series. I can't even guess where that might be.


    upload_2023-8-24_15-9-34.png
     
  21. Bill_G

    Bill_G New Member

    It's a 3G83 engine.

    Based on your suggestion earlier in the thread, I did try spraying carb cleaner directly into the throat when the engine started to die. When the carb cleaner went in, the engine continued running. So, it acts like it is starving for fuel.

    The length of time it runs has me believing the fuel shut-off solenoid is faulty, as the engine always runs for 5-8 seconds each time it starts. That never varies.

    The diagram you included looks like the solenoid on my truck. It is located on top of the carb, but it looks like it will have to be removed from the passenger side. I am really hesitant to remove the carburetor, due to all the hoses, and electrical connections. If the carb was in an open area, where it was easy to take photos or mark the connections, it would be different. The darned thing is really difficult to access. I suspect that someone who works on them regularly has a system and they don't dread it as much.

    I thought about splicing the wires and running power from the battery, but if it is defective the symtoms would not change and I would just have to repair the wiring. When I have a chance, I will try to remove the solenoid and test it. Should be able to see if it is working when power is supplied.

    Thanks again for all your help.
     
  22. MikeD

    MikeD Member

    Great info. Based on all of this you're certainly on the right track....bad fuel, solenoid, gunked up carb, etc. There shouldn't be a need to splice the wires...yet........ chances are it's getting power but it's so gunked up the plunger isnt working.

    You could get a cheap test light . Ground the test light and probe the connection, that will be the test for power. If it's getting power then it's gunked up. If no power then you can diagnose further.


    When we say shut off solenoid are we taking about the same thing ? Is it a separate safety switch or a plunger in the carb bowl that cuts off the fuel when powered.?

    Is the fuel line going into the carb easy to reach ?

    Sounds like it's too hard to get the carb off ? Not to mention the need to possibly replace seals and what not?

    Have you tried the mechanic in a bottle fuel additive yet ? Probably pointless to put it in the tank since fuel may not be getting delivered but if you could get some right into the carb and try get it running for a few seconds . Then let it sit oveu. No promises here but I've seen it work wonders in these scenarios where the carb can't come off.

    Just thinking out loud here idk .....
     
  23. Bill_G

    Bill_G New Member

    The test light is a good idea. I have a multimeter, may be able to get probes to the wires without taking it off.

    I believe we are talking about the same thing (fuel cut-off solenoid). It looks like the part shown in the diagram you posted. I believe it was designed to stop fuel flow in the event of a collision or over-turned vehicle. I am thinking it has a plunger that stops the flow of fuel to the engine when the power is cut/off.

    The fuel line into the carb is fairly easy to get to. I've had it off a couple of times to check flow.

    Have not tried Mechanic In A Bottle yet. But that is still a consideration. As per your suggestion, if I had a way to get it into the carb, it may do some good.

    All good thoughts that I will keep in mind. The discouraging part is that the little truck has never failed to start and run in the 15 years that I have owned it. Now, when I need to move it, I run into this. I guess these things happen, but it's really bad timing.

    Thanks again for your insight and suggestions.
     
  24. MikeD

    MikeD Member

    You may just have to start thinking about loading it on a trailer or getting it moved without running it, if you don't have much time left.
     
  25. Bill_G

    Bill_G New Member

    That's plan B, Mike.


    Thanks!
     
  26. Nathan Marshall

    Nathan Marshall New Member

    Any resolution yet? Mine started doing a similar thing last week. I wonder about floats in the carb being stuck. Seems the accelerator pump will still feed fuel, but opening the throttle enough to get it to squirt will quickly bog it down
     
  27. Bill_G

    Bill_G New Member

    No resolution. I replaced the fuel cut-off solenoid and suspect that was the problem. However, afterwards when I tried starting it, the engine turned over, but didn't attempt to start. I removed the fuel line from the carb and found that no fuel was getting to it. This had never been an issue in the past, so not sure if the fuel pump stopped working or what happened.

    Long story short, I ran out of time to get it moved and sold the truck to a neighbor, cheap. A really disappointing outcome.

    Best of luck resolving your issue. The folks at G&R Imports were a tremendous help to me.
     
  28. dmerc444

    dmerc444 New Member

    Anyone having this problem in the future, try a small temporary vented tank (from lawnmower,m/c, plastic bottle,...etc) hooked to carb. Simple gravity draining. with known fresh gas, would bypass many variables re: fuel, pump, fuel cutoff,....etc
     

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